– The milecastle was scheduled as an ancient monument. 1999 – An excavation is undertaken by English Heritage consisting of two trenches, one through the eastern wall and interior and one through the southern wall. The eastern wall was noticeably robbed but found to be of stone, bonded by clay, with a rubble core. The excavation discovered that the floor was made of sandy clay or else this formed the basis for a later earthen floor, and that it was cobbled in the western portion of the interior. Finds recovered included some ironwork, modern glass, an animal bone, one Roman Sestertius of Emperor Hadrian dating from AD 125–138 and pottery (some pre-Roman, but mostly 2nd/3rd century AD). The archaeologists were able to confirm that the milecastle was of narrow wall construction. The milecastle was noted to have been damaged by ploughing. The altar discovered, in a 2nd-century AD context, in the 1930s led Birley to suggest that there was a shrine located nearby or that the milecastle had later been converted to religious use. The size of the altar suggests that the temple would have been very small. Though altars are not uncommon on Hadrian's Wall, there are 13 other altars or tombs located near to milecastles, it is an inscription on the altar at Milecastle 19 that makes it important to Roman historians. The inscription reads "MATRIB TEMPL CVM ARA VEX COH I VARD INSTANTE P D V VSLM" which translates as "to the Mother Goddesses, this temple with its altarstone [was built by] a detachment of the First Cohort of Varduli, under P[ublius] D[omitius?] V[?], willingly and deservedly fulfilling their vow". The dedication to the Matres, or mother goddesses is one of only 60 known from Roman Britain. The First Cohort of Varduli are also mentioned in inscriptions at the Antonine Wall, Longovicium in Durham, Bremenium and Corstopitum in Northumberland and on the Dere Street in Cappuck in the Scottish Borders. The Vardullians are known to have been present at Corbridge in the AD 160s. The inscription has led to debate amongst archaeologists as to whether Hadrian's Wall was manned by Roman legionaries or men of the non-citizen auxilia or numeri. Birley suggested that those soldiers who were tasked with manning the wall were drawn from separate units from those who manned the supporting forts. The altar itself is recorded as a separate monument to the milecastle by